title: Comparison of histological lesions in mink with acute hemorrhagic pneumonia associated with Pseudomonas aeruginosa or Escherichia coli.
abstract: Hemorrhagic pneumonia can be a major cause of mortality in farmed mink in the fall. In its classic form, hemorrhagic pneumonia is caused by the bacterium Pseudomonas aeruginosa. In recent years, however, outbreaks of this type of pneumonia that are associated with hemolytic Escherichia coli have also occurred in farmed mink. The purpose of this study was to compare histological lesions of acute hemorrhagic pneumonia associated with both P. aeruginosa and E. coli in mink, including a description of tissue distribution of pathogens, in an attempt to differentiate between the 2 disease entities based on histopathology. The study included material submitted for diagnostic investigation to the National Veterinary Institute in Denmark from 2006 to 2009. Altogether, 19 cases of hemorrhagic pneumonia with a pure lung culture of P. aeruginosa and 18 cases of hemorrhagic pneumonia with a pure lung culture of E. coli were examined. Formalin-fixed paraffin-embedded lung tissue obtained from the mink was examined by histology and fluorescence in-situ hybridization (FISH). It was possible to detect a slight histological difference between hemorrhagic pneumonia caused by P. aeruginosa and by E. coli, as P. aeruginosa was most often found surrounding blood vessels and lining the alveoli, while E. coli showed a more diffuse distribution in the lung tissue. Furthermore, P. aeruginosa often elicited a very hemorrhagic response in the lung, while infection with E. coli was associated with a higher frequency of alveolar edema and mild lymphoid cuffing in the lungs.
authors.affiliation: National Veterinary Institute, Technical University of Denmark, Hangoevej 2, DK-8200 Aarhus N., Denmark (Salomonsen, Jensen, Hammer) and Bülowsvej 27, DK-1870 Frederiksberg C., Denmark (Boye); Department of Clinical Microbiology, Rigshospitalet, Blegdamsvej 9, DK-2100 Copenhagen Ø, Denmark (Høiby).
authors.forename: Charlotte Mark
authors.initials: CM
authors.lastname: Salomonsen
authors.forename: Mette
authors.initials: M
authors.lastname: Boye
authors.forename: Niels
authors.initials: N
authors.lastname: Høiby
authors.forename: Trine H
authors.initials: TH
authors.lastname: Jensen
authors.forename: Anne Sofie
authors.initials: AS
authors.lastname: Hammer
mesh_terms: D000818:Animals; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D003718:Denmark; D004196:Disease Outbreaks / Q000662:veterinary; D004926:Escherichia coli / Q000235:genetics / Q000276:immunology*; D004927:Escherichia coli Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D006651:Histocytochemistry / Q000662:veterinary; D017404:In Situ Hybridization, Fluorescence / Q000662:veterinary; D008168:Lung / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D008907:Mink / Q000276:immunology / Q000382:microbiology*; D011014:Pneumonia / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011552:Pseudomonas Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000276:immunology*
chemical_list: D004269:DNA, Bacterial